Effect of the addition of Sm2O3 on the microstructure of laser cladding alloy coating layers

• Published in: Metals and materials international Vol. 14; no. 3; pp. 315 - 319
• Main Authors: Zhang, Shi Hong, Li, Ming Xi, Cho, Tong Yul, Yoon, Jae Hong, Fang, Wei, Joo, Yun Kon, Kang, Jin Ho, Lee, Chan Gyu
• Format: Journal Article
• Language: English
• Published: Seoul The Korean Institute of Metals and Materials 01-06-2008; Springer Nature B.V; 대한금속·재료학회
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Engineering Thermodynamics; Heat and Mass Transfer; Machines; Magnetic Materials; Magnetism; Manufacturing; Materials Science; Metallic Materials; Processes; Protective coatings; Solid Mechanics; 재료공학; laser cladding; microstructure; rapid solidification; micron-sized and nano-sized Sm; Ni-based alloy; O
• ISSN: 1598-9623; 2005-4149
• DOI: 10.3365/met.mat.2008.06.315

The effects on the microstructures and phases of coating layers by the addition of micron-sized (m) and nano-sized (n) (m&n) Sm
2
O
3
powders were investigated. The coating materials, which were prepared by means of 2.0 kW CO
2
laser cladding, consist of a powder mixture of m Ni-based alloy (NBA) powders comprising 1.5 wt.% m Sm
2
O
3
and 3.0% n Sm
2
O
3
powders. The results indicate that γ-Ni, Cr
23
C
6
and Ni
3
B are the primary phases of the NBA coatings. The Fe
7
Sm and Ni
3
Si phases are highlighted by the addition of m&n Sm
2
O
3
powders. From the substrate, planar crystal layers are first grown in all NBA and m&n Sm
2
O
3
/NBA coatings. The dendrite growth then occurs as a result of the addition of the m Sm
2
O
3
powder, and the equiaxed dendrite growth occurs as a result of the addition of the n Sm
2
O
3
. With the addition of a rare earth oxide such as Sm
2
O
3
powder, the width of the planar crystal becomes smaller than that of the NBA coating.